GnRH agonist and hCG (dual trigger) versus hCG trigger for final follicular maturation: a double-blinded, randomized controlled study

STUDY QUESTION

Does co-administration of GnRH agonist and Human chorionic gonadotropin (hCG; dual trigger) in IVF cycles improve the number of mature oocytes and pregnancy outcome compared to hCG alone?

SUMMARY ANSWER

Using the dual trigger for final follicular maturation increases the number of oocytes, mature oocytes and number of blastocysts (total and top-quality) compared to triggering with hCG alone.

WHAT IS KNOWN ALREADY

hCG is used at the end of controlled ovarian hyperstimulation as a surrogate LH surge to induce final oocyte maturation. Recently, based on retrospective studies, the co-administration of GnRH agonist and hCG for final oocyte maturation (dual trigger) has been suggested to improve IVF outcome and pregnancy rates.

STUDY DESIGN, SIZE, DURATION

A single center, randomized controlled, double-blinded clinical trial between May 2016 and June 2018 analyzed by intention to treat (ITT).

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

One hundred and fifty-five normal responder patients were randomized either to receive hCG or dual trigger for final oocyte maturation. Data on patients age, BMI, AMH, number of oocytes retrieved, number of metaphase 2 (MII) oocytes, zygotes and blastocysts, clinical pregnancy rate and live birth rate were assessed and compared between the dual trigger group and the hCG group. We performed a planned interim analysis after the recruitment of 50% of the patients. Based on the totality of outcomes at the interim analysis we decided to discontinue further recruitment.

MAIN RESULTS AND THE ROLE OF CHANCE

One hundred and fifty-five patients were included in the study. The age (36 years versus 35.3 years P = NS), BMI (24 kg/m2 versus 23.7 kg/m2) and the AMH (20.1 pmol/l versus 22.4 pmol/l) were comparable between the two groups. Based on ITT analysis, the number of eggs retrieved (11.1 versus 13.4, P = 0.002), the MII oocytes (8.6 versus 10.3, P = 0.009), total number of blastocysts (2.9 versus 3.9, P = 0.01) and top-quality blastocysts transferred (44.7% versus 64.9%; P = 0.003) were significantly higher in the dual trigger group compared to the hCG group. The clinical pregnancy rate (24.3% versus 46.1%, OR 2.65 (1.43-1.93), P = 0.009) and the live birth rate per transfer (22% versus 36.2%, OR= 1.98 (1.05-3.75), P = 0.03) were significantly higher in the dual trigger group compared to the hCG group.

LIMITATIONS, REASONS FOR CAUTION

None.

WIDER IMPLICATIONS OF THE FINDINGS

The enhanced response observed with the dual trigger might lead to better IVF outcomes were it used more widely.

STUDY FUNDING/COMPETING INTEREST(S)

The study was funded by TRIO Fertility. There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov identifier: NCT02703584.

DATE OF TRIAL REGISTRATION

March 2016.

DATE OF FIRST PATIENT'S ENROLLMENT

May 2016.

Eye-blink conditioning deficits indicate temporal processing abnormalities in schizophrenia

Theoretical models suggest that symptoms of schizophrenia may be due to a dysfunctional modulatory system associated with the cerebellum. Although it has long been known that the cerebellum plays a critical role in associative learning and motor timing, recent evidence suggests that it also plays a role in nonmotor psychological processes. Indeed, cerebellar anomalies in schizophrenia have been linked to cognitive dysfunction and poor long-term outcome. To test the hypothesis that schizophrenia is associated with cerebellar dysfunction, cerebellar-dependent, delay eye-blink conditioning was examined in 62 individuals with schizophrenia and 62 age-matched non-psychiatric comparison subjects. The conditioned stimulus was a 400 ms tone, which co-terminated with a 50 ms unconditioned stimulus air puff. A subset of participants (25 with schizophrenia and 29 controls) also completed the Wechsler Abbreviated Scale of Intelligence. Participants with schizophrenia exhibited lower rates of eye-blink conditioning, including earlier (less adaptively timed) conditioned response latencies. Cognitive functioning was correlated with the rate of conditioned responsing in the non-psychiatric comparison subjects but not among those with schizophrenia, and the magnitude of these correlations significantly differed between groups. These findings are consistent with models of schizophrenia in which disruptions within the cortico-cerebellar-thalamic-cortical (CCTC) brain circuit are postulated to underlie the cognitive fragmentation that characterizes the disorder.

Eyeblink conditioning anomalies in bipolar disorder suggest cerebellar dysfunction

OBJECTIVES

Accumulating research implicates the cerebellum in non-motor psychological processes and psychiatric diseases, including bipolar disorder (BD). Despite recent evidence that cerebellar lesions have been documented to trigger bipolar-like symptoms, few studies have directly examined the functional integrity of the cerebellum in those afflicted with BD.

METHODS

Using a single-cue delay eyeblink conditioning procedure, the functional integrity of the cerebellum was examined in 28 individuals with BD (9 manic, 8 mixed, and 11 euthymic) and 28 age-matched healthy controls.

RESULTS

Analysis of the bipolar group as a whole indicated a conditioned response acquisition and timing deficit compared to controls. However, when the bipolar group was categorized according to mood state (mixed, manic, euthymic), individuals tested during mixed episodes were strikingly impaired, performing significantly worse than all other groups on both the acquisition and timing of conditioned responses.

CONCLUSIONS

These findings extend prior research implicating cerebellar functional abnormalities in BD and suggest that cerebellar dysfunction may be associated with mood state and course of illness.

Interaction of heavy metal toxicants with brain constitutive nitric oxide synthase

This study was designed to evaluate the in vitro effects of transition heavy metal cations on activity of constitutive isoform of nitric oxide synthase (cNOS) in rat brain. NOS activity was determined in the cytosolic fractions of rat cerebral hemispheres by conversion of 3H-L-arginine to 3H-L-citrulline. Different concentrations of mercury (Hg2+), nickel (Ni2+), manganese (Mn2+), zinc (Zn2+), cadmium (Cd2+), lead (Pd2+) and calcium (Ca2+) were tested on NOS activity. While all the cations caused inhibition, there were differences in the apparent inhibition constants (Ki) among the cations. With the exception of calcium ion no other cation required preincubation with the enzyme preparation. These results indicate that while calcium ion modulate cNOS activity at regulatory site(s), inhibitory influence of toxic heavy metal cations may be exerted on the catalytic site(s) either by direct binding to it or by interfering with the electron transfer during catalysis.

Cerebellar-dependent eyeblink conditioning deficits in schizophrenia spectrum disorders

Accumulating evidence suggests that abnormalities in neural circuitry and timing associated with the cerebellum may play a role in the pathophysiology of schizophrenia. Schizotypal personality disorder (SPD) may be genetically linked to schizophrenia, but individuals with SPD are freer from potential research confounds and may therefore offer insight into psychophysiological correlates of schizophrenia. The present study employed a delay eyeblink conditioning (EBC) procedure to examine cerebellar-dependent learning in schizophrenia, SPD, and healthy control subjects (n = 18 per group) who were matched for age and gender. The conditioned stimulus was a 400-ms tone that coterminated with a 50 ms unconditioned stimulus air puff. Cognitive performance on the Picture Completion, Digit Symbol Coding, Similarities, and Digit Span subscales of the Wechsler Adult Intelligence Scale--Third Edition was also investigated. The schizophrenia and SPD groups demonstrated robust EBC impairment relative to the control subjects; they had significantly fewer conditioned responses (CRs), as well as smaller CR amplitudes. Schizophrenia subjects showed cognitive impairment across subscales compared with SPD and control subjects; SPD subjects showed intermediate performance to schizophrenia and control subjects and performed significantly worse than controls on Picture Completion. Impaired EBC was significantly related to decreased processing speed in schizophrenia spectrum subjects. These findings support the role of altered cortico-cerebellar-thalamic-cortical circuitry in the pathophysiology of schizophrenia spectrum disorders.

Power comparisons for tests of trend in dose-response studies

The Cochran-Armitage test for trend is a popular statistical procedure for detecting increasing or decreasing probabilities of response when a categorical exposure is ordered. Such associations may arise in a variety of biomedical research settings, particularly in dose-response designs such as carcinogenicity experiments. Previously, computing limitations mandated the use of the asymptotic trend test, but with the availability of new algorithms, increased computing power, and appropriate software the exact trend test is now a practical option. Nevertheless, the exact test is sometimes criticized on the grounds that it is conservative. In this paper we investigate the implications of this conservatism by comparing the true type I error and power of three alternative tests of trend - the asymptotic test, the exact test and an admissible exact test proposed by Cohen and Sackrowitz. The computations are performed by an extension to the network algorithm of Mehta et al. This allows us to make precise power comparisons between the tests under any given design without resorting to simulation. We show how this tool can guide investigators in choosing the most appropriate test by considering the design of two-year carcinogenicity studies carried out by the National Toxicology Program. We additionally compare the tests for various other combinations of sample sizes and number of groups or levels of exposure. We conclude that the asymptotic test, while more powerful where it is valid, generally does not preserve the type I error. This violation of the a priori testing level can be greatly affected by imbalance in the data or unequal spacing of dose levels.

Sodium thiosulfate protects against acrylonitrile-induced elevation of glial fibrillary acidic protein levels by replenishing glutathione

Acrylonitrile (ACN) like many organic solvents produce neurotoxicity by elevating brain glial fibrillary acidic protein (GFAP), a putative biomarker of astrogliosis. In this study we tested the hypothesis that sodium thiosulfate (STS) protective action against ACN-induced astrogliosis is glutathione (GSH) mediated. Male Sprague-Dawley rats were administered for 2 weeks intraperitoneal doses (50 mg/kg body weight) of the ACN, with or without STS as outline in the Methods section. Specific brain regions were tested for GFAP, GSH and glutathione-S-transferase (GST) enzyme activity. In the brain regions tested STS significantly (P</=0.05) maintained GFAP levels at the basal saline control levels, when compared to ACN-treated groups. STS also significantly (P</=0.05) increased GSH levels in these brain regions with a corresponding increased in GST enzyme activity. Although the data indicated that STS antidotal action against ACN-induced neurotoxicity is likely to involve GSH and GST activity, other complex series of mechanisms may be involved.

An exact trend test for correlated binary data

The problem of testing a dose-response relationship in the presence of exchangeably correlated binary data has been addressed using a variety of models. Most commonly used approaches are derived from likelihood or generalized estimating equations and rely on large-sample theory to justify their inferences. However, while earlier work has determined that these methods may perform poorly for small or sparse samples, there are few alternatives available to those faced with such data. We propose an exact trend test for exchangeably correlated binary data when groups of correlated observations are ordered. This exact approach is based on an exponential model derived by Molenberghs and Ryan (1999) and Ryan and Molenberghs (1999) and provides natural analogues to Fisher's exact test and the binomial trend test when the data are correlated. We use a graphical method with which one can efficiently compute the exact tail distribution and apply the test to two examples.

Computational tools for exact conditional logistic regression

Logistic regression analyses are often challenged by the inability of unconditional likelihood-based approximations to yield consistent, valid estimates and p-values for model parameters. This can be due to sparseness or separability in the data. Conditional logistic regression, though useful in such situations, can also be computationally unfeasible when the sample size or number of explanatory covariates is large. We review recent developments that allow efficient approximate conditional inference, including Monte Carlo sampling and saddlepoint approximations. We demonstrate through real examples that these methods enable the analysis of significantly larger and more complex data sets. We find in this investigation that for these moderately large data sets Monte Carlo seems a better alternative, as it provides unbiased estimates of the exact results and can be executed in less CPU time than can the single saddlepoint approximation. Moreover, the double saddlepoint approximation, while computationally the easiest to obtain, offers little practical advantage. It produces unreliable results and cannot be computed when a maximum likelihood solution does not exist.

Enhancement of mitogen response and surface marker analysis of lymphocytes from young and old donors after preliminary incubation in vitro

We have examined the detailed kinetics of PHA induced proliferation of freshly isolated mononuclear cells from young and old human donors. Our studies confirm that donors over the age of 60 years may have a decreased number of PHA responsive cells and that these cells have a significantly diminished rate of entry into the first cell cycle. Age of the donor does not affect the time at which significant numbers of cells appear in first S-phase, the duration of first S-phase, the doubling time in exponential growth, and thymidine uptake per cell. Cells from young and old donors were also cultured in medium supplemented with pooled human serum for 1 or 2 days prior to the PHA response assay. After 2 days of preliminary culture, the PHA response in both young and old is significantly enhanced, with a greater enhancement in the old. The basis of this enhancement appears to be a significant increase in rate of entry into the first cell cycle. None of the other kinetic parameters were significantly altered. The magnitude of the rate enhancement in old donors' cells eliminated the difference in entry rate between young and old after 2 days of preliminary culture. The same rate enhancing effects were seen in the presence of serum pooled from young or old donors. There is no statistically significant change in the number of responding cells after preliminary culture. We had previously suggested, based on lactate dehydrogenase (LD) subunit ratio and patterns of T cell associated surface markers, that less differentiated subpopulations of T cells exist in elderly donors. After preliminary culture, no significant change was seen in the proportions of cells positive for T3, T4, T8, T10 and Ia surface antigens and the unusual pattern of surface marker distribution was still present on the old donors' cells. It appears that the greater rate enhancement in old donors' cells after preliminary culture may not be due to induced maturation of the possibly less differentiated T cell populations described previously. The results do suggest that these subpopulations may be non-responsive to PHA.

Power and sample size for ordered categorical data

We propose a new method for computing power and sample size for linear rank tests of differences between two ordered multinomial populations. The method is flexible in that it is applicable to any general alternative hypothesis and for any choice of rank scores. We show that the method, though asymptotic, closely approximates existing exact methods. At the same time it overcomes the computational limitations of the exact methods. This advantage makes our asymptotic approach more practical for sample size computations at the planning stages of a large study. We illustrate the method with data arising from both proportional and non-proportional odds models in the two ordered multinomial setting.

Exploration of cerebellar-dependent associative learning in schizophrenia: effects of varying and shifting interstimulus interval on eyeblink conditioning

Eyeblink conditioning abnormalities have been reported in schizophrenia, but the extent to which these anomalies are evident across a range of delay intervals (i.e., interstimulus intervals; ISIs) is unknown. In addition, the effects of ISI shifts on learning are unknown, though such manipulations can be informative about the plasticity of cerebellar timing functions. Therefore, the primary purpose of the present study was to investigate the interactions between ISI manipulations and learning in schizophrenia. A standard delay eyeblink conditioning procedure with four different interstimulus intervals (ISIs; 250, 350, 550, 850 ms) was employed. Each eyeblink conditioning experiment was immediately followed by another with a different ISI, thus permitting the characterization of conditioned response (CR) learning at one ISI and the extent to which CRs could be generated at a different latency following an ISI shift. Collapsing across all conditions, the schizophrenia group (n = 55) had significantly fewer conditioned responses and longer onset latencies than age-matched controls (n = 55). Surprisingly, shifting to a new ISI had negligible effects on conditioned response rates in both groups. These findings contribute to evidence of robust eyeblink conditioning abnormalities in schizophrenia and suggest impaired cerebellar function, but underscore the need for more research to clarify the source of these abnormalities and their relationship to clinical manifestations of schizophrenia.

Preparation and evaluation of a sustained morphine delivery system in rats

A new drug delivery system to induce physical dependence to morphine in rats is described. The device consists of a silicone polymer containing a water soluble "carrier" material, sodium alginate, which swells on contact with moisture to release the drug. The silicone or silastic pellets formulated to contain morphine sulfate are very easily prepared and the advantages over existing methods to induce physical dependence to morphine are discussed. In addition, a comparison of the percent of drug released and withdrawal intensities in rats was made with a silastic-morphine sulfate pellet, silastic-morphine base pellet and a microcrystalline cellulose-morphine base pellet.

Homozygosity in the major histocompatibility complex region influences natural killer cell activity in man

The effect of homozygosity at HLA loci on natural killer (NK) cell activity has been examined. Lymphocytes obtained from heterozygous and homozygous individuals were incubated with 51Cr-labeled, NK-sensitive K562 cells at different effector/target ratios, and lytic activity was determined. Homozygous cells, obtained from individuals who are known HLA homozygotes (homozygous typing cells) and from selected families, had low NK activity compared to those heterozygous donors. This low cytotoxic activity had no correlation with sex, but did correlate with homozygosity at the HLA-A, B and/or DR loci. A significantly lower number of cells, which bind to anti-Leu 7 antibody, was found in homozygous donors. However, this reduced number of Leu 7+ cells could only partially account for the decrease in NK activity. These studies suggest that in some individuals homozygosity at HLA may be linked to genes that control NK activity.

Sustained release of alcohol: subcutaneous silastic implants in mice

A sustained-release device for use in ethanol dependence studies in mice is described. The Silastic device, dubbed SERT (sustained ethanol release tube), holds 0.35 milliliter of 95 percent ethanol (by volume) and is implanted under the skin of the back where it releases ethanol for up to 12 hours, with no observable tissue damage. The device may be adaptable to the release of other volatile liquids or drugs, in other animals.

Rapid and sensitive quantitative immunoassay for the large simian virus 40 T antigen

A quantitative, enzyme-linked immunoadsorbent assay has been developed for the simian virus 40 large T antigen. When hamster anti-simian virus 40 tumor serum was used, this method permitted specific identification of large T antigen and its analog, the D2 hybrid protein, a molecule with the same C-terminal approximately 600 amino acids as large T antigen. The sensitivity limit of this test was 0.63 ng of protein. The slopes of the regression lines of the enzyme-linked immunosorbent assay titrations performed with highly purified D2 or simian virus 40 large T antigen and with crude extracts of simian virus 40-infected monkey and transformed human cells were identical. Thus, the curve generated with a purified protein, such as D2, can serve as a quantitative standard for the measurement of large T antigen in a wide variety of extracts. Furthermore, solutions containing high salt concentrations and buffers containing up to 0.1% Nonidet P-40 did not interfere with the assay, making it applicable to the measurement of large T antigen in a variety of chromatographic fractions. The enzyme-linked immunosorbent assay was three times more sensitive, was significantly faster to perform, and was quantitatively valid over a much broader large-T-antigen concentration range than the complement fixation test. As such, it should be useful in future studies of the structure and function of this protein.

Effects of acute and continuous administration of morphine on the cyclic AMP response induced by norepinephrine in rat brain slices

Pre-incubated cortical brain slices from adult male Sprague Dawley rats when challenged by exogenous norepinephrine (NE) exhibited a dose-dependent increase in the level of endogenous cyclic 3',5' adenosine monophosphate (cyclic AMP), with the maximal response elicited at 50 microM NE concentration. The administration of 50 mg/kg sub-cutaneous (Sub-Q) morphine 5 minutes before sacrifice significantly increased the responsiveness of the brain slices to the NE-induced cyclic AMP response at 0.5, 5.0, and 50.0 microM NE. Sustained administration of morphine from the subcutaneously implanted morphine pellet (75 mg morphine base) attenuated the potentiated cyclic AMP response to NE in the brain slices of the rats exposed to a single challenge dose of 50 mg/kg (Sub-Q) morphine 5 minutes before sacrifice. This tolerance or attenuated response is first observed 24 hours after morphine pellet implantation with maximal tolerance observed at 48 hours after the pellet implantation. A complete reversal of attenuated NE-induced cyclic AMP response was observed when the 3 day morphine implanted rats were injected with a challenge dose of naloxone (4 mg/kg, Sub-Q) at 10 minutes prior to the acute administration of 50 mg/kg Sub-Q injection of morphine 5 minutes before sacrifice. These results suggest that both acute and prolonged administration of morphine alters NE-induced cyclic AMP response of the brain slices, and that naloxone, an opioid antagonist, reverses this response. This is perhaps due to morphine-induced alterations in the availability of NE in the CNS.

Flexible bronchoscopic removal of a three piece foreign body from a child's bronchus

Foreign body aspiration can be a life-threatening event especially in young children because they have smaller diameters of airway lumen, moreover, the delay in the diagnosis and subsequent therapeutic intervention can further increase the risk of morbidity.(1, 2) A retained foreign body can result in inflammatory response and granulation tissue formation around the object which make the foreign body removal difficult.(3) In such situations surgical intervention is usually needed but with interventional pulmonology modalities we can restrict the need for surgery.(4) Rigid bronchoscopy under general anaesthesia is the gold standard of diagnosis and management of foreign body aspiration.(1) However, nowadays flexible bronchoscopy is more widely available and most pulmonary physicians are trained in its use so it can be used to remove such foreign bodies. We hereby report a case of a neglected foreign body which remained in the bronchus of a child for 11 days, successfully removed by flexible bronchoscopy.

Chronic administration of cyanide: urinary excretion of thiocyanate in male and female rats

The urinary elimination of thiocyanate was investigated in male and female rats following the chronic administration of potassium cyanide. Female rats dosed at the level of 5 mg KCN/kg once a week and twice a week respectively, displayed no significant difference in the excretion of thiocyanate in urine after periods of up to eight weeks of study. Similarly, male rats that were administered 5 mg/KCN/kg twice weekly showed no significant difference in the amount of thiocyanate excreted. The elimination patterns of thiocyanate in male and female rats showed no significant differences. The results suggest that a substrate saturation phenomenon is not operative with cyanide metabolism at the dosage level of potassium cyanide employed in this study. This is contrary to a previously published study which reported that the urinary excretion of thiocyanate decreased after chronic potassium cyanide administration.